tests : initial memcmp and memcpy unaligned benchmarks

Summary:
We were missing unaligned benchmarks for memcmp and memcpy.
These are basic and unaligned by +10/+13 making them very aggressively
unaligned.

Test Plan:
make sure I didn't miss anything. Possibly move printing into
the original functions so we don't need entirely new functions and can
unalign there.

Reviewers: randall.rushing, synergy

Reviewed By: synergy

Differential Revision: http://review.codefirex.com/D451